The present invention relates to a film-forming agent or, more particularly, to a film-forming agent useful as an ingredient in skin-care preparations and polishing agents or in medical uses.
It is a remarkable fact that certain people having frequent daily occasions of handling water, such as medical doctors, nurses, cooks, housewives and the like, sometimes suffer from skin chapping or inflammation on their hands and fingers because the skin on their hands and fingers is apt to be defatted by water, in particular, water containing a detergent. It is a usual practice in order to protect hands and fingers from skin chapping that a skin-care preparation is applied to the hands and fingers after contacting with water. Such a skin-care treatment is of course very troublesome if each time of water handling must be followed by application of a skin care preparation. Accordingly, several attempts and proposals have been made to develop a skin care preparation capable of exhibiting sustained water repellency (see, for example, Japanese Patent Publication 48 1503 and Japanese Patent Kokai 61-161209, 61-161211 and 61-161214).
For example, the skin-care preparation disclosed in Japanese Patent Publication 48-1503 contains a diorgano polysiloxane terminated at each molecular chain end with a trimethyl silyl group and having a relatively high viscosity. The skin care preparation of this type is not quite satisfactory in the feeling of use because, when it is applied to human skin, tackiness is felt more or less in addition to the poor sustainability of water repellency far from sufficient.
Turning now to polishing agents such as, mainly, car polishing waxes, sustainability of water repellency is also a desirable characteristic thereof and various products have been developed from this standpoint (see, for example, Japanese Patent Kokai 59-30876). The improvement in the sustainability of water repellency in these products is obtained to some extent by utilizing a silicone resin to serve simultaneously as a water repellency-imparting ingredient and as a film forming agent but the improvement obtained thereby is still not satisfactory.